1. Field of the Disclosure
This invention is related to image sensors. More specifically, examples of the present invention are related to wafer level packaging of image sensors.
2. Background
Image sensors have become ubiquitous. They are widely used in digital still cameras, cellular phones, security cameras, as well as, medical, automobile, and other applications. The technology used to manufacture image sensors, and in particular, complementary metal-oxide-semiconductor (CMOS) image sensors (CIS), has continued to advance at a great pace. For example, the demands for higher resolution and lower power consumption have encouraged the further miniaturization and integration of these image sensors.
Image sensors are typically implemented with supporting internal circuitry within integrated circuit packages that are mounted onto printed circuit boards. The image sensors are typically illuminated with light through a protective glass cover located on a top surface of the integrated circuit package. One of the major challenges with image sensors is the continuing effort to reduce the size and cost of the packages in which the image sensors are implemented. As image sensor technology continues to advance, there is an increasing desire to reduce the thickness and footprint of the imaging packages on printed circuit boards to create smaller, thinner, and lighter electronic devices.
Corresponding reference characters indicate corresponding components throughout the several views of the drawings. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.